The invention resides in a press tool for installation in different presses.
It is known that press tools in particular in connection with large-part presses are subjected to bending under the effect of the press pressure. The bending is load-dependent. The tool is designed to bend by a certain pre-calculated amount.
The bending tool parts are supported by the press table or, respectively, the press plunger. With the bending of the tool parts also the press table and/or press plunger is subjected to a certain amount of bending. The finally occurring bending therefore does not depend only on the load effective on the tool (press force), but also on the rigidity properties of the plunger and/or the press table.
It has already been tried to prevent the bending of the tool by totally compensating for it. To this end, DE 44 15 577 A1 proposes a support plate which includes several hydraulic actuators. The actuators are controlled by means of a hydraulic system which again is controlled by a distance or bending sensor, for controlling the pressure applied to the compensation pistons. The publication assumes that the press table and the press plunger are subjected to bending which is fully compensated for by the hydraulic activators so that neither the upper nor the lower tool part experience any bending when they are subjected to load.
The actively controlled tool support plate requires, however, an additional installation space which reduces from the free height present between the plunger and the tool table. In addition, the use of the compensation plate requires tools which are designed to basically not bend during use. Such tools, however, are not usable without a corresponding compensation plate because of the then unavoidable bending. They must, therefore, be designed specifically for use in connection with a corresponding compensation plate.
Based on this state of the art, it is the object of the present invention to provide a possibility for controlling the bending of the tool in a simple manner.